Michael Fuhr <mike@fuhr.org> writes:
> Unless I'm missing something that wouldn't use an index either,
> because the planner wouldn't know what value to compare start_date
> against without hitting each row to find that row's time_to_live.
> But something like this should be able to use an expression index
> on (start_date + time_to_live):
> WHERE start_date + time_to_live < now()
Or perhaps simpler, get rid of time_to_live in favor of an end_date
column, which could be indexed directly.
regards, tom lane
